$-2fg - 2fh - 9f - 6 = 8g + 2$ Solve for $f$.
Solution: Combine constant terms on the right. $-2fg - 2fh - 9f - {6} = 8g + {2}$ $-2fg - 2fh - 9f = 8g + {8}$ Notice that all the terms on the left-hand side of the equation have $f$ in them. $-2{f}g - 2{f}h - 9{f} = 8g + 8$ Factor out the $f$ ${f} \cdot \left( -2g - 2h - 9 \right) = 8g + 8$ Isolate the $f$ $f \cdot \left( -{2g - 2h - 9} \right) = 8g + 8$ $f = \dfrac{ 8g + 8 }{ -{2g - 2h - 9} }$ We can simplify this by multiplying the top and bottom by $-1$. $f= \dfrac{-8g - 8}{2g + 2h + 9}$